In LTE Release 8 (Rel-8), e.g. for reducing the size or configuration of handover command message (e.g. radio resource controller (RRC) connection reconfiguration message), 3GPP decided to use the so-called delta signaling. This means that in case a target eNB does not include e.g. a parameter in the handover command, a user equipment (UE) may assume that the parameter or function will continue after the handover.
However, in the current universal mobile telecommunication system (UMTS) (e.g. so-called 3G system), e.g. the so-called inter-radio network controller (RNC) handover does not use this kind of scheme, but in case of a UE involving e.g. radio network system (RNS) relocation (e.g. hard handover), a target RNC may constructs a handover command message based on the radio access bearer (RAB) information. This means that the target RNC may explicitly include parameters to be used after the handover.
There have been approaches dedicated to solve the above issues.
For example, a full signaling configuration may be used. However, in 3GPP, there are no considerations on how the target eNB may choose usage of either a so-called delta signaling or full signaling.
However, the delta signaling assumes that the source eNB and the target eNB are using the same RRC protocol release or target eNB RRC protocol release is newer than the one of the source eNB. However, e.g. in case that the target eNB RRC protocol release is earlier than that of the source eNB, an additional rule may be required because by no means can the target eNB continue a later release functionality after the handover. Thus, all additional functionality and parameters defined in later release may be released.
In consideration of the above, according to the example of the present invention, methods, apparatuses, a related computer program product and a data structure for deciding on a signaling scheme for handover are provided.
In this connection, the examples of the present invention enable one or more of the following:
Specifying a logic for the target eNB to choose usage of either delta signaling or full signaling;
Enabling a parameter exchange to assist the target eNB in making the above decision;
Avoiding a complicated network, and thus, avoiding a complicated operation and management (O&M) configuration effort;
Providing a simple logic for the target eNB dealing on when to use delta signaling and when to use full configuration signaling.